Downgrade emacs from 25.0.50 into 24.5.1 introduce error on startup

Question

The error is as follows

Warning (emacs): Unable to activate package `flycheck'.
Required package `seq-1.11' is unavailable
Warning (emacs): Unable to activate package `beacon'.
Required package `seq-1.11' is unavailable
Warning (emacs): Unable to activate package `flycheck'.
Required package `seq-1.11' is unavailable
Warning (emacs): Unable to activate package `beacon'.
Required package `seq-1.11' is unavailable

Is that the only way to deal with it is to recompile the .emacs.d file? If yes, how can I do that. Thank you

Answer 1

It looks like you need the seq package. According to its webpage, its included in Emacs 25 by default, so you already had it with Emacs 25.0.50. It's not in Emacs 24, so after you downgraded you need to install it from the Elpa repository.